Glaucoma is a disease of the eye that affects millions of people. Glaucoma is associated with an increase in intraocular pressure resulting either from a failure of a drainage system of an eye to adequately remove aqueous humor from an anterior chamber of the eye or overproduction of aqueous humor by a ciliary body in the eye. Build-up of aqueous humor and resulting intraocular pressure may result in irreversible damage to the optic nerve and the retina, which may lead to irreversible retinal damage and blindness.
Glaucoma may be treated by surgical intervention that involves placing a shunt in the eye to result in production of fluid flow pathways between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). Such fluid flow pathways allow for aqueous humor to exit the anterior chamber. Generally, the surgical intervention to implant the shunt involves inserting into the eye a deployment device that holds an intraocular shunt, and deploying the shunt within the eye. A deployment device holding the shunt enters the eye through a cornea (ab interno approach), and is advanced across the anterior chamber. The deployment device is advanced through the sclera until a distal portion of the device is in proximity to a drainage structure of the eye. The shunt is then deployed from the deployment device, producing a conduit between the anterior chamber and various structures of the eye involved in aqueous humor drainage (e.g., Schlemm's canal, the sclera, or the subconjunctival space). See for example, Prywes (U.S. Pat. No. 6,007,511).
A problem associated with such surgical interventions is ensuring that placement of the shunt does not change during deployment of the shunt from the deployment device. Deployment devices that are used to place the shunt in the eye generally rely on multiple moving components in order to deploy the shunt. Movement of the components of the deployment device shifts the position of the deployment device within the eye during the deployment process, and thus shifts the position of the shunt as it is being deployed. Such movement leads to improper placement of the shunt within the eye.